A braking device for a vehicle is equipped with a master cylinder, an output piston which varies the volume of a master chamber by being driven by a force corresponding to a hydraulic pressure in a servo chamber, an input piston defining a first hydraulic pressure chamber to be filled with a brake fluid with the output piston and operable in association with an operation of a brake operating member, a mechanical servo pressure generating device which outputs a hydraulic pressure corresponding to a higher hydraulic pressure between the hydraulic pressure inputted to a first pilot chamber and a hydraulic pressure inputted to a second pilot chamber, a pilot pressure generating device which generates a hydraulic pressure corresponding to an inputted control signal in the first pilot chamber and a passage connecting the master chamber and the second pilot chamber. This type of the braking device for a vehicle is, for example, described in a patent publication JP2011-240873 A.